import React from "react";

class App extends React.PureComponent {
  constructor(props) {
    super(props);

    this.state = {
      obj: { number: 0 },
    };
  }

  handleChange = () => {

  };

  render() {
    console.log("件渲染了", this.state.obj.number);
    return (
      <div>
        <h2>{this.state.obj.number}</h2>
        <button onClick={this.handleChange}>
          修改
        </button>
      </div>
    );
  }


}


export default App;
